Strep throat is an infection of the pharynx caused by the bacteria Streptococcus pyogenes. The pharynx is the part of the throat between the tonsils and the larynx, or voice box.
What is going on in the body?
Strep throat is the most common of the many infections that are caused by group A streptococci, or GAS. The bacteria that causes strep throat makes a toxin that results in an infection in the throat and tonsils. A person can develop symptoms of strep throat from 1 to 6 days after being exposed to the bacteria. Symptoms in up to 40% of children may be too mild to diagnosis. Up to 20% of school-aged children may be carriers of the bacteria. These children will show no symptoms but can transmit strep throat to others.
A sore throat accompanied by fever is caused by a virus 70% of the time. Without treatment, uncomplicated viral infections usually subside within 3 to 10 days after onset. Strep throat is more significant because of the increased incidence of complications.
What are the causes and risks of the disease?
Strep throat is a bacterial infection that is usually spread by person-to-person contact through coughing or sneezing. Exposure to a person who has untreated strep throat may pose a risk for acquiring this infection. A person may be a carrier of the strep bacteria without having symptoms.
People who may be more at risk for serious strep infection include the following:
people who have chronic conditions or diseases such as diabetes
people who have weakened immune systems, such as those with HIV or immunodeficiency disorders
children who have chickenpox
Symptoms & Signs
What are the signs and symptoms of the disease?
The following are symptoms of strep throat:
sore throat that starts suddenly, without runny nose or congestion
“fiery” red throat
white patches on the tonsils
swollen lymph nodes in the neck
fever, with a temperature of 101 to 104 degrees Fahrenheit, or 38.3 to 40 degrees celsius
loss of appetite
Children with strep throat may also have these additional symptoms:
Diagnosis & Tests
How is the disease diagnosed?
Strep throat may be suspected after a medical history and physical exam are performed. The back of the throat is swabbed to get a sample of the bacteria. Tests that may be done on this sample are
ELISA, or “quick strep,” which makes it possible to make the diagnosis within 15 minutes
throat culture, which involves the growing of bacteria and takes at least 24 hours
Blood tests, including a complete blood count orCBC, may also be done to check for infection.
Prevention & Expectations
What can be done to prevent the disease?
Strep throat can be spread from person to person. Prompt diagnosis and treatment is the best way to prevent the disease and its complications. Anyone with strep throat should take antibiotics for at least 24 hours before returning to work, school, or day care. In addition, hands should be washed thoroughly and soiled tissues should be discarded promptly.
What are the long-term effects of the disease?
In most cases, there are no long-term effects from strep throat. Complications may occur if a strep infection is not treated, including the following:
ear infections, such as acute otitis media
tonsillitis, with abscesses or damage to the tonsils
scarlet fever, a rash associated with strep throat
rheumatic fever, an inflammation of the joints and the heart that can cause heart damage
poststreptococcal glomerulonephritis, an inflammation of the kidney that can lead to kidney damage
What are the risks to others?
Anyone with an untreated strep throat can spread it to others.
Treatment & Monitoring
What are the treatments for the disease?
Penicillin is the usual treatment for strep throat. If a person is allergic to penicillin, another antibiotic may be used. To prevent the complications of strep infections, it is important to take the entire course of antibiotics prescribed, even if the symptoms subside.
Following are ways to reduce symptoms:
rest, especially when fever is present
warm salt-water gargles and throat lozenges to reduce pain and inflammation
over-the-counter pain medications, such as acetaminophen, for pain and fever
plenty of liquids. Iced drinks or milk shakes, as well as a soft-foods diet, may help to relieve discomfort.
Aspirin should not be given to children or teens, as it increases the risk of a serious disorder known as Reye’s syndrome.
What are the side effects of the treatments?
The most common side effects of antibiotics are stomach upset, rash, and allergic reaction.
What happens after treatment for the disease?
Most strep throat infections respond rapidly to treatment. Usually no further treatment is needed.
How is the disease monitored?
Any new or worsening symptoms should also be reported to the healthcare provider.